Scientists Have Learned When Early Gray Hair Goes Away By Itself
You can get rid of gray hair naturally, scientists have found. Isolated cases of this transformation were known before. But, judging by the latest works, almost any early graying person can do this. Now experts are trying to understand the mechanism of this process.
Usually, people start to go gray after 35 years, but much depends on genetic predisposition and gender. So, women's heads turn white later than men's, and Europeans with the first gray hair can face almost 20 years earlier than people from Africa and Asia. However, between 45 and 65 years of age, gray hair is already noticeable in almost everyone. According to researchers, 74 percent of people by this age have gray hair that covers almost a third of their heads.
The most common explanation is aging. It is believed that with age, hair loses color due to the depletion of hair bulbs, or rather the death of melanocytes located in them, cells that produce two forms of the pigment melanin, eumelanin, and pheomelanin. It depends on them whether a person will be blond, brown-haired, dark-haired, or red.
Sometimes gray hair is associated with a health condition or stress. So, it is proved that a lack of vitamin B12, vitiligo-a violation of pigmentation in certain areas of the skin — and thyroid diseases contribute to the formation of gray strands. Besides, violations of the innate immune system can speed up the process.
Back in the 1980s, biologists found out that if mice in the womb are infected with the mouse leukemia virus, they will turn gray very quickly after birth. This means that problems with pigmentation somehow correlate with innate immunity, but it was not clear exactly how.
Only in 2018, US researchers discovered that one of the proteins, MITF, which regulates the production of melanin in melanocytes, is also linked to genes that control the innate immune system. In experiments in mice in which melanocytes were absent from this protein, was synthesized too much of interferons. These substances provoke an immune response when a virus enters the cell. Their excess disrupted the production of melanocytes themselves, which caused the mice to have gray hairs.
Despite the skepticism of some experts, scientists have described several cases when the hair turned white overnight. According to researchers at Harvard University (USA), most likely, stress contributes to the loss of stem cells-precursors of melanocytes, which are contained in hair follicles. As a result, the pigment is no longer produced, and the hair loses color.
Biologists injected black lab mice with a toxin that causes them extreme physiological stress. After injections, the level of corticosterone in rodents increased three times, and norepinephrine-ten times. Both of these hormones are strongly formed in a stressful situation.
At the same time, the mice that received the toxin along with the analgesic had the same amount of corticosterone and norepinephrine as the animals from the control group — they were not injected with the toxin.
After the injection, the rodents were shaved to speed up hair growth. After a couple of weeks, a new coat appeared, but it was almost 30 percent gray. Further experiments showed that under stress, melanocyte progenitor cells disappeared from the follicles, which caused rapid graying.
The role of a mediator was made by noradrenaline.
As the authors suggest, in a stressful situation, the body releases norepinephrine, which causes stem cells, which should turn into melanocytes, to divide and migrate.
Usually, these cells reproduce rarely, but when the process is accelerated, their resources are quickly depleted. Also, stem cells may leave the follicle altogether or be unable to replenish the supply of melanocytes. This leads to the loss of pigmentation and gray hair.
Free of preservatives and artificial colors
However, it is this stressful gray hair that is reversible, scientists from Columbia University (USA) are sure. They studied 397 individual hairs taken from 14 healthy volunteers of different ages and backgrounds. Some specimens were completely grey, others only partially so.
Researchers, focusing on the average speed of hair growth-about a centimeter per month, compared the color of individual areas with certain periods of life of their owners and events that occurred.
It turned out that at a relatively young age, gray hair often occurs due to stress. And as soon as the situation normalizes, the hair returns to its original color. This happened to a 35-year-old European whose hair was studied in this work.
Besides, experts found a similar relationship when analyzing the two-color hair of a thirty-year-old Asian woman. The formation of the two-centimeter-long gray area coincided with a breakdown in her family, divorce, and forced relocation. After returning to normal life, the hair color was completely restored.
In total, we counted more than ten cases of such reversible graying in people aged nine to 39 years. On average, recovery took the same amount of time as a color loss — about three months. And not only on the head but also on the rest of the body.
According to the authors, this suggests that other mechanisms of human aging may be partially reversible. But to find out, you must first understand how and why the hair returns to its original color. This is what researchers will do in the coming years.